As a photosensitive material for an ArF resist, for example, a radiation sensitive material comprising a resin (A) having at least one polar group-containing alicyclic functional group, and a substance (B) having at least one functional group capable of generating an alkali-soluble group through an acid in a molecule is known. A copolymer of a mono- or trihydroxyadamantyl methacrylate and t-butyl methacrylate is listed as the resin (A) and the resin is a resin which has transparency to an excimer laser and is excellent in developing properties and dry etching resistance (see Patent Document 1).
Also, it is known that an acrylic acid-based polymer having a low molecular weight and narrow molecular weight distribution is useful as a photosensitive material for an ArF resist (see Patent Document 2)    Patent Document 1: Japanese Unexamined Patent Application, First Publication No. Hei 11-109632    Patent Document 2: Japanese Unexamined Patent Application, First Publication No. 2003-82010